1. Field of the Invention
The present invention relates to an image processing apparatus which executes various processing operations of an input image to perform image edit operations.
2. Related Background Art
In a conventional digital copying machine, an original is illuminated with a halogen lamp or the like, and light reflected by the original is color-separated into, e.g., R (red), G (green), and B (blue) by an optical means such as an optical filter or a prism. The R, G, and B signals are photoelectrically converted to electrical signals using a charge-coupled device such as a CCD. The electrical signals are then converted into digital signals, and the digital signals are subjected to predetermined processing. Thereafter, an image is formed using a recording apparatus such as a laser beam printer, a liquid crystal printer, a thermal printer, an ink-jet printer, or the like.
In a digital copying machine of this type, requirements for outputting smooth images, and outputting sharp characters and lines have been demanded, and extensive studies have been made to meet such requirements.
However, in an area gradation system in which gradation of an image is assured by a dot area, gradation of an output image conflicts with a resolution level, and different processing operations must be performed for an image portion and a character portion. Although many systems have been introduced so far, complex software processing must be executed in most of them. Some real-time processing systems become very expensive due to their circuit scales, and are not suitable for commercial products.